Synergistic Reinforcement Of Lignin–Chitosan Hydrogels Using Vanillin As A Sustainable Green Crosslinker, Moses Ayitey-Adjin Jr., Mohammad Jahid Hasan, Jeremy Erb, Kishore Chand, Garry S. Crosson, Kenya Crosson, Esteban Ureña-Benavides, Erick Salvador Vasquez-Guardado

Chemical and Materials Engineering Faculty Publications

While bio-based hydrogels derived from lignin and chitosan are promising sustainable adsorbents, their practical application is hindered by poor mechanical stability. This study addresses this limitation by synthesizing lignin-chitosan hydrogels using vanillin as a green, bio-derived crosslinker via a facile solution-casting method. The formation of imine (Schiff base) linkages between the aldehyde groups of vanillin and the primary amines of chitosan was confirmed by FTIR spectroscopy (C = N stretching at ~ 1602 cm^− 1). SEM and TGA results demonstrated a reduction in the pore size of the crosslinked hydrogel and an enhanced residual thermal mass. Rheological and …

Electrospinning Of Covalent Organic Frameworks (Cofs) For Adsorption Of Heavy Metal Ions, Samar A. Salim

Nanotechnology Research Centre

This study reported the synthesis, electrospinning, and heavy metal adsorption of covalent organic frameworks (COFs) integrated into poly(methyl methacrylate) (PMMA) nanofibers. COF-1 and COF-2 were synthesized by solvothermal and reflux techniques, respectively, and subsequently incorporated into PMMA via electrospinning with different loadings (0.1%, 0.5%, and 1.0%). The synthesized PMMA_COF nanofibers were analyzed utilizing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and diffuse reflectance spectroscopy (DRS). PMMA_COF nanofibers with fiber diameters of 350-450 nm were obtained. The structural and morphological investigations validated the effective integration of COFs into the PMMA matrix, with COF-1 demonstrating superior dispersion …

Magnetic Cellulose Nanocrystal Composites: Synthesis, Properties, Applications, And Opportunities, Mohammad Jahid Hasan, Kishore Chand, Esteban E. Ureña-Benavides, Erick S. Vasquez-Guardado

Chemical and Materials Engineering Faculty Publications

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Magnetic Cellulose Nanocrystal Composites: Synthesis, Properties, Applications, and Opportunities

Metal Oxide Nanoparticle‑Integrated Phema Hydrogels: Morphology, Chemical Properties, And Biological Interaction, Venkateswar Rao, Collin Cox, Brandon Clark, Arushi Rai, Erick S. Vasquez-Guardado, Madhuri Kango-Singh, Soubantika Palchoudhury

Chemical and Materials Engineering Faculty Publications

Hydrogels offer attractive matrices for incorporating inorganic metal oxide nanoparticles (NPs) to generate multifunctional hybrid materials, but challenges remain in scalable synthesis and correlating their properties to bio-interaction. Therefore, we report the synthesis and characterization of poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogels, and pHEMA hydrogels encapsulating iron oxide or zinc oxide NPs, using a modified free-radical polymerization. Dose-dependent survivorship studies on Drosophila melanogaster revealed that both NP-embedded hydrogels are tolerated over a wide dose range (e.g., 50–200 mg), although ZnO NP-gels exhibit lower survivorship at some concentrations due to their inherent composition and a wider size distribution of iron oxide NPs.

A Performance-Weighted Environmental Assessment Of Ultra-High-Volume Fly Ash Substitution In Portland Cement Concrete, Youngguk Seo, M.A. Karim, Teddy Tzvetkov, Joshua Hardy

Faculty Articles

Fly ash substitution for cement in Portland cement concrete (PCC) has been regarded as a sustainable solution, but its widespread application remains constrained by concerns over mechanical performance and durability of PCC, especially at higher replacement rates. This study evaluates PCC mixes incorporating fly ash Type C (FA-C) or Type F (FA-F) across cement replacement rates from 10% to 90%, tracking fresh-state workability, compressive strength, and surface electrical resistivity at 7, 14, and 28 curing days. A process-based life cycle assessment (LCA) with the TRACI 2.1 method quantified global warming potential (GWP, kg CO₂/m³) under a …

Polymer-Derived Silicon Oxycarbide (Sioc) And Silicon Carbonitride (Sicn) Ceramics For Advanced Electrochemical Energy Storage Applications, Saja Al Ajrash, Erick S. Vasquez-Guardado

Chemical and Materials Engineering Faculty Publications

Preceramic polymers, especially silicon oxycarbide (SiOC) and silicon carbonitride (SiCN) ceramics, have gained significant attention due to their wide range of applications in many fields, particularly in energy storage devices beyond conventional lithium-ion batteries (LIBs). This review focuses on the synthesis, structural characteristics, and properties of SiOC and SiCN ceramics as electrodes for battery applications. Furthermore, their promising applications as electrode materials for energy storage systems are explored, along with the most recent advances in the development of such materials and their use in lithium-ion batteries (LIBs), lithium-sulfur batteries (LSBs), potassium-ion batteries (PIBs), sodium-ion batteries (SIBs), and supercapacitors. This review …

Self-Assembly Interactions In Magnetite-Coated Cellulose Nanocrystals: Implications For Magnetic Hyperthermia Applications, Mohammad J. Hasan, Erin L. Mcneill, Kishore Chand, Juganta Roy, Monishita Deb, Katherine Schlaak, Sydney Herzog, Yvonne Sun, Sarah Watzman, Esteban E. Ureña-Benavides, Erick S. Vasquez-Guardado

Chemical and Materials Engineering Faculty Publications

Magnetic cellulose nanocrystal (MCNC) nanocomposites are promising sustainable and biocompatible platforms for magnetic hyperthermia; however, the molecular mechanisms governing Fe3O4 adsorption and deposition onto CNCs remain poorly understood. Here, sulfated (S-CNC) and TEMPO-oxidized CNCs (T-CNC) were used to prepare nanocomposites at 1:2 and 1:4 CNC:Fe3O4 mass ratios, enabling a systematic evaluation of how surface chemistry and nanoparticle loading dictate interfacial interactions and magneto-colloidal behavior. Bare magnetite nanoparticles were 21 ± 5 nm by TEM but grew to 144 ± 18 in the DLS measurement at pH 7. The S-CNC nanocomposites had hydrodynamic sizes between 144 and 210 nm, not much …

Data Set, R Scripts And Script Outputs For Manuscript: Manufacturing Systems: Characteristics And Dynamics, Alan J. Fitzmorris

Graduate Research Data

This file repository contains fifteen computer-generated datasets, two naturally occurring datasets, nineteen shipbuilding shop datasets, and sixty-one concrete plant datasets.  Each data set contains subdirectories associated with various aspects of the data analysis, including stationarity analysis, dynamic system analysis, and complexity analysis.  In each case, applicable R scripts are included.  The text file entitled “Directory_and_File_Names” depicts the directory structure and associated file names for a total of 225 directories encompassing 8008 files.

Few-Layered Conductive Graphene Foams For Electrical Transdifferentiation Of Mesenchymal Stem Cells Into Schwann Cell-Like Phenotypes, Ekin G. Simsar, Peifu Cheng, Tugce Dogruel, Maxsam Donta, Juhyung Jung, Naomi A. Asante, Donald S. Sakaguchi, Surya K. Mallapragada, Piran R. Kidambi, Metin Uz

Chemical & Biomedical Engineering Faculty Publications

This study investigates the potential of few-layered conductive graphene foams as 3D platforms for the electrical transdifferentiation of mesenchymal stem cells (MSCs) into Schwann cell (SC)-like phenotypes for peripheral nerve injury (PNI) treatment. The 3D graphene foams (3D-GF) are cytocompatible with MSCs and created a favorable microenvironment for the cells to attach, grow, proliferate, and transdifferentiate. We demonstrated that MSCs cultured within 3D-GF can be transdifferentiated into SC-like phenotypes using the synergistic effects of electrical stimulation and 3D porous and conductive structure. Our immunocytochemistry and gene expression analyses showed the expression of Schwann cell markers and enhanced secretion of growth …

Engaging Students In Materials Engineering Through A Marble-Based Property Ranking Game, Nathan Cloughley, Alyssa Felix

College of Engineering Summer Undergraduate Research Program

This SURP proposal is centered on the design and development of a Materials Marbles Game, an educational tool designed to introduce students to materials science and materials selection through tactile interaction and hands-on experimentation. The game will incorporate measurement of key material properties—such as mechanical, thermal, electrical, and mass density—using spherical marbles made from different materials. These measurements will then be used to construct a physical Material Property Chart (Ashby-Cebon plot) on a game board, fostering a hands-on, embodied understanding of how different materials behave. The game will also illustrate the thought process behind materials selection, a critical aspect of …

Synthesis And Characterization Of Temperature- And Ph-Responsive Pia-B-Pnipam@Fe3O4 Nanocomposites, Swati Kumari, Cayla Cook, Fatema Tarannum, Erick Salvador Vasquez-Guardado, Olufemi Ogunjimi, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

Stimuli-responsive polymers (SRPs) have garnered significant attention in recent decades due to their immense potential in biomedical and environmental applications. When these SRPs are grafted onto magnetic nanoparticles, they form multifunctional nanocomposites capable of various complex applications, such as targeted drug delivery, advanced separations, and magnetic resonance imaging. In this study, we employed a one-step hydrothermal method using 3-aminopropyltrimethoxysilane (APTES) to synthesize APTES-modified Fe₃O₄ nanoparticles (APTES@Fe₃O₄) featuring reactive terminal amine groups. Subsequently, via two consecutive surface-initiated atom transfer radical polymerizations (SI-ATRP), pH- and temperature-responsive polymer blocks were grown from the Fe₃O …

Magnetic Nanoparticles: Synthesis And Applications In Life Sciences, Kishore Chand, Erick Salvador Vasquez

Chemical and Materials Engineering Faculty Publications

Magnetic nanoparticles (MNPs) are multifunctional materials with superparamagnetic properties and tunable surface chemistries, making them valuable across diverse fields, such as biomedicine, environmental remediation, and agriculture. This review examines recent advancements in MNP synthesis, encompassing chemical, physical, and environmentally friendly methods while highlighting improvements in size, morphology, and composition control that enhance application-specific performance and environmental sustainability. The review discusses various architectures, including single-core, core–shell, hybrid composites, and stimuli–responsive systems, with an emphasis on their stability, scalability, and functionalization potential. In biomedical applications, MNPs show promise in targeted drug delivery, magnetic hyperthermia, and magnetic resonance imaging contrast enhancement, where biocompatibility, …

Work In Progress: Exploring The Impact Of International Experiences On The Development Of Students’ Entrepreneurial Mindset, Olgha Bassam Qaqish, Marcia Pool, William H. Pennock, Erick Salvador Vasquez, Fahmidah Ummul Ashraf

Chemical and Materials Engineering Faculty Publications

International experiences, including collaborative online international learning (COIL) experiences that naturally increase accessibility, are of interest to many undergraduate students. These experiences provide educators a unique opportunity to develop a student's entrepreneurial mindset (EM). Additionally, hands-on experiences aligned with the National Academy of Engineering’s (NAE) grand challenge themes (Sustainability, Security, Health, and Joy of Living) support connections between the experience, disciplinary knowledge, multicultural awareness, and EM. Through this Work-in-Progress (WiP) study, we seek to answer: 1) How do international experiences influence undergraduate science and engineering students’ EM, and 2) How does the international experience modality (i.e., study abroad or COIL) …

Camino—Career Advancement, Mentorship, Inspiration, And Opportunities: A Stem K-12 Outreach Initiative, Hector A. Pulgar, Francisco Zelaya-Arrazabal, Erick Salvador Vasquez, Sebastian N. Martinez Lizana

Chemical and Materials Engineering Faculty Publications

CAMINO is a STEM program designed to promote career advancement, provide mentorship, give inspiration, and offer opportunities for K-12 Hispanic students located in East Tennessee. As part of the educational component of an NSF CAREER grant, the program launched in 2021 and is a collaboration between a research group from the University of Tennessee and one of the high schools with the largest Hispanic populations in the Knoxville Metropolitan area. These students from minority backgrounds may limit their aspirations and may not pursue higher education and/or professional development for numerous reasons, such as limited motivation, insufficient exposure to higher education, …

Entrepreneurially Minded Learning (Eml) Micromoment Activities Generated Using Students' Experiences In A Fluid Flow And Heat Transfer Course, Erick Salvador Vasquez, Megan Morin

Chemical and Materials Engineering Faculty Publications

The Entrepreneurially Minded Learning (EML) Framework involves the 3 C's: curiosity, connections, and creating value. Several design courses, open-ended assignments, and laboratory experiences can successfully lead to EML implementations. However, these implementations require extensive class time and instructor feedback, limiting their use in core engineering courses. Developing EML activities that are active, engaging, and rapid to deploy in a classroom setting can promote the sustained growth of an entrepreneurial mindset (EM). EML micromoment activities are emerging as a practical tool to facilitate the incorporation of the 3 Cs through rapid activity implementations that only last 2 – 30 minutes. These …

Shrinkage Study In Photopolymerisable Hybrid Sol-Gel Through Holographic Patterning, Jamshed Aftab, Izabela Naydenova, Tatsiana Mikulchyk

Articles

Photopolymerisation induced shrinkage of holographic materials is one of the main factors which needs to be considered for designing holographic optical elements (HOEs) with high accuracy in light redirection with maximum efficiency. This work studies the shrinkage in photopolymerisable hybrid sol-gel (PHSG) by examining the properties of volume transmission gratings recorded in PHSG layers. It explores both the dependence of shrinkage on the holographic grating parameters (thickness, spatial frequency, slant angle) and the effect of material aging. By using the fringe-plane rotation model, shrinkage is found to have the maximum value of 1.37 % at 765 lines/mm (19.36° slant angle) …

Student-Led Video Podcasting In A Chemical Behavior Of Materials Course, Erick Salvador Vasquez

Chemical and Materials Engineering Faculty Publications

Video podcasts, or vodcasts, are a form of podcasting that combines video and audio to deliver various types of educational content effectively. To our knowledge, very few studies have focused on student-produced podcasting for learning technical engineering concepts. This study explores using student-created technical videos in a course on the chemical behavior of materials through three separate assignments. The first assignment centered on sustainability aspects. Students, divided into groups of three, were tasked to review two influential journal articles on plastic waste input into the ocean and metal recycling. Each group had to prepare and deliver a technical script about …

Low-Field Magnetoresistance In Nanocomposites Of La₀.₇Sr₀.₃Mno₃ And Metal Oxides, Nicholas K. Thiel-Hudson

University Scholar Projects

Pure La_0.7Sr_0.3MnO₃ (LSMO) exhibits colossal magnetoresistance (CMR) with large applied magnetic field over a narrow temperature range (intrinsic behavior), limiting its application to narrow temperature ranges. In contrast, the extrinsic CMR effect originates from inhomogeneities at larger length scales, such as grain boundaries and phase separation, where the structural features act as tunneling barriers, leading to a low-field magnetoresistance (LFMR) response, thereby expanding the application of LSMO into the low-field regime over a broader temperature range. In this work, the magnetotransport behavior of pure LSMO thin film is compared to the composite layered heterostructures of …

A High-Temperature Lithium-Aluminum Alloy/Oxygen Or Air Fuel Cell, Sarwan S. Sandhu

Chemical and Materials Engineering Faculty Publications

This paper is in support of our current effort in the development of an experimental hybrid (lithium- aluminum alloy/electrolyte/oxygen or air) fuel cell for the acquisition of the experimental data required to characterize its performance behavior. The literature-based assembled formulation provided in this paper can be used to predict the cell open-circuit electric potential, lithium amount in the cell anode alloy, and g-atom ratio of lithium to aluminum in the cell anode as a function of time at any cell discharge current level. The ohmic voltage losses can also be computed in the cell cathode, anode, and two electrolytes at …

Scalable Mxene-Based Textile Supercapacitors, Abaigeal Aydt

Honors Program: Senior Projects (Public)

The demand for flexible and wearable energy storage devices for portable applications has led to the exploration of textile-based supercapacitors (TSCs). TSCs will allow for the creation of a new class of energy harvesting and storing technology directly into our clothing and will require using non-toxic and/or biocompatible materials. This will result in a greener and more sustainable path to address the challenges at the nexus of energy, mobility, and sustainability. To fabricate a TSC, a yarn made of fibers, such as wool or cotton, is coated with MXene flakes; MXenes are composed of transition metal carbides, nitrides, or carbonitrides …

Biobased Acrylate Composites With Enhanced Strength For Additive Manufacturing, Nicole Wagner, Joseph Mcwherter

Engineering Faculty Articles and Research

With the expanding use of polymers in additive manufacturing, sustainable resins for use in vat photopolymerization are required to reduce their environmental impact. One promising approach to achieve this is to incorporate biobased fillers that replace the acrylates in photopolymer resins as ‘green’ alternatives. In this study, photopolymer composites consisting of a methacrylate resin with varying calcium carbonate powder content between 0 and 50 wt.% were investigated. A digital light processing technique was used to fabricate tensile test specimens for mechanical testing. Good printability, dimensional accuracy, and good interlayer adhesion were observed for composite resin formulations that incorporated calcium carbonate …

Advances In Magnetic Nanoparticles For Molecular Medicine, Xiaoyue Yang, Sarah E. Kubican, Zhongchao Yi, Sheng Tong

Markey Cancer Center Faculty Publications

Magnetic nanoparticles (MNPs) are highly versatile nanomaterials in nanomedicine, owing to their diverse magnetic properties, which can be tailored through variations in size, shape, composition, and exposure to inductive magnetic fields. Over four decades of research have led to the clinical approval or ongoing trials of several MNP formulations, fueling continued innovation. Beyond traditional applications in drug delivery, imaging, and cancer hyperthermia, MNPs have increasingly advanced into molecular medicine. Under external magnetic fields, MNPs can generate mechano- or thermal stimuli to modulate individual molecules or cells deep within tissue, offering precise, remote control of biological processes at cellular and molecular …

Investigation Of Conductive Die-Top Thermal Capacitors During Short Circuit Operation Of Silicon Carbide Devices, Youssef Abotaleb

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Silicon carbide (SiC) power devices have garnered significant attention in recent years due to their superior thermal and electrical properties compared to traditional silicon devices. However, SiC power devices suffer from severe reliability issues arising from their mechanical properties. This is because the Young's modulus of SiC is about three times larger than that of silicon, which correspondingly raises the mechanical stresses acting on the bonding structure, often leading to device failure under power shock events.

Traditional packaging materials and designs tend to constrain SiC performance, as hot-spot temperature resulting from a power shock is one of the key factors …

Solubility Characterization Of Organic Molecules For Aqueous Organic Redox Flow Batteries, Anthony W. Ferrell, Harkeerith K. Vij, Seamus D. Jones

College of Engineering Summer Undergraduate Research Program

The major obstacle to renewable energy sources is a lack of long-term energy storage capabilities. Energy produced during the day dissipates, leaving insufficient electricity for at night. The goal of the project is to design an Aqueous Organic Redox Flow Battery (AORFB) to act as long-term energy storage. Work has been done using machine learning to identify suitable compounds for the batteries. In this work there was no indication as to the aqueous solubility of the molecules; this controls the device’s energy storage capabilities. We used a machine learning model to determine the aqueous solubility of slightly more than 3000 …

Deep-Learning Based Microstructure Reconstruction And Generation, Cameron J. Maloney, Lucas Taliaferro

College of Engineering Summer Undergraduate Research Program

Characterizing the microstructural behavior of materials is crucial for understanding their properties and performance. Traditional imaging methods, such as optical microscopy and electron microscopy, are effective but costly and time-consuming. Computational approaches can reduce costs and time while expanding the accessibility of microstructural analysis through the generation of new microstructure images. Traditional computational approaches, namely descriptor-based approaches, are slow but effective in low-data scenarios. Modern approaches use machine learning (ML), which is faster but often requires a lot of data to approach the performance of descriptor-based methods. This research leverages a special data-efficient Generative Adversarial Network (GAN) architecture to artificially …

Assessing Global Engagement Interventions To Advance Global Engineering Competence For Engineering Formation, Scott Schneider, Erick S. Vasquez-Guardado, Corinne Mowrey, Michael Moulton, Homero Murzi, Matthew A. Witenstein

Chemical and Materials Engineering Faculty Publications

This paper summarizes the work performed during the first year of a collaborative Research Initiation in Engineering Formation (RIEF) project focused on assessing the formation of a global learner mindset in engineering students through the use of different types of global engagement interventions without extended international travel. During this year the global engagement interventions have been developed, piloted, and assessed using the Global Engagement Survey (GES) and Global Engineering Competency Scale (GECS) instruments in a pre and post format. The assessment results helped the research team update the interventions and refine the assessment strategy, including the addition of new qualitative …

Work In Progress: Exploring The Impact Of International Experiences On The Development Of Students’ Entrepreneurial Mindset, Olgha Bassam Qaqish, Marcia Poole, William Pennock, Erick S. Vasquez-Guardado, Fahmidah Ummul Ashraf

Chemical and Materials Engineering Faculty Publications

International experiences, including collaborative online international learning (COIL) experiences that naturally increase accessibility, are of interest to many undergraduate students. These experiences provide educators a unique opportunity to develop a student's entrepreneurial mindset (EM). Additionally, hands-on experiences aligned with the National Academy of Engineering’s (NAE) grand challenge themes (Sustainability, Security, Health, and Joy of Living) support connections between the experience, disciplinary knowledge, multicultural awareness, and EM. Through this Work-in-Progress (WiP) study, we seek to answer: 1) How do international experiences influence undergraduate science and engineering students’ EM, and 2) How does the international experience modality (i.e., study abroad or COIL) …

Enhancing Entrepreneurial Minded Learning Of Process Control And Heat Transfer Concepts Using Micromoments And Concept Maps, Erick S. Vasquez-Guardado, Ricardo Gomez Gonzalez, Jean M. Andino, Nilza D. Aples, Xiaojing Yuan

Chemical and Materials Engineering Faculty Publications

The Entrepreneurially Minded Learning (EML) Framework seeks to infuse an Entrepreneurial Mindset in engineering students. The EML framework is founded on the 3 C’s principles of curiosity, connections, and creating value. Assessing EML efforts, however, is a well-known challenge for many engineering courses that do not have a design component. Through concept maps and micromoment activities, this work seeks to answer the following questions: Does implementing micromoment activities enhance students’ EML in two core areas of chemical engineering, i.e., heat transfer and process controls? A secondary research question is whether introducing a physical device in lectures enhances students’ EML. The …

Using Micromoments And Concept Maps To Enhance Entrepreneurially Minded Learning Of Indoor Air Pollution Control, Jean M. Andino, Erick Salvador Vasquez-Guardado, Ricardo Gomez Gonzalez, Xiaojing Yuan, Nilza D. Aples

Chemical and Materials Engineering Faculty Publications

Micromoments targeted toward indoor air quality were introduced to students in an Air Quality Engineering course to enhance their entrepreneurial mindset. Three micromoment activities, i.e., “Question Frenzy”, “Make It Relevant”, and “How Do We Make It Better?” that are linked, respectively, to the curiosity, connections, and creating value elements of EM were deployed in the class in the context of the use of a Corsi Rosenthal cube (a do-it-yourself structure that has recently become popular as an inexpensive way to reduce indoor particle pollution). Students generated concept maps pre-and post- micromoment intervention using the freely available CMap Tools software. The …

Free And Forced Vibrations Of Elastically Restrained Cantilever With Lumped Oscillator, Alireza Babaei, Johné Parker, Paria Moshaver

Earth and Environmental Sciences Faculty Publications

The efficiency assessment of cantilever-based energy harvesters relies on vibrational analysis, which necessitates modi- fications aimed at enhancing efficiency. These modifications involve manipulating the fundamental frequency to lower values and encompassing a wider range of resonances within a specified bandwidth. Consequently, this paper introduces an original analytical-numerical exploration into the vibratory response of a cantilever with a novel boundary condi- tion involving an elastically restrained oscillator-spring arrangement. At the microbeam’s tip, an oscillator is elastically confined by a linear spring, resulting in a novel set of coupled governing equations and a distinct shearing boundary condition. Microbeam equations is derived from …